Swedes in Frongoch

Brassica napus subsp. napobrassica

Swede
Swede · Brassica napus subsp. napobrassica

A hardy root crop for the UK, swedes do best in firm, fertile soil that has been well dug and cleared of stones. Sow outdoors in late spring to early summer, thin carefully, and keep the plants covered with fine mesh to reduce cabbage root fly damage. Lift roots from autumn onwards, and leave some in the ground where the soil drains well for harvests through winter.

40 cm · Full Sun · Moderate Water

Add to garden

Calibrated to Frongoch · last frost ≈ 29 May

Sow June to July, harvest October to January. Frost risk October to May.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
SowNoNoNoNoNoYesYesNoNoNoNoNo
HarvestYesNoNoNoNoNoNoNoNoYesYesYes

Growing guide

Step-by-step instructions for growing Swede

  1. 01

    Prepare the Bed

    29 May to 12 Jun

    Dig the soil deeply and remove stones, then rake it to a fine, even finish for 29th May - 12th June. Do not add fresh manure, as it can make roots fork and split.

  2. 02

    Sow Seeds

    5 Jun to 10 Jul every 3 weeks

    Sow seeds thinly in shallow drills around 5th June - 10th July, then water the row in well. Keep the soil moist while seedlings establish, and sow a second short row 21 days later if you want a longer harvest period.

  3. 03

    Protect from Pests

    5 Jun to 10 Jul

    Cover the bed with fine insect-proof mesh from 5th June straight after sowing. Seal the edges well to keep out cabbage root fly and remove the cover only for weeding or thinning.

  4. 04

    Thin Seedlings

    13 Jul to 20 Jul

    From 13th July - 20th July, thin seedlings gradually to the final spacing so the roots can swell properly. Water the bed first, then remove the weakest plants with a small pull rather than disturbing the rest.

  5. 05

    Water and Weed

    20 Jul to 3 Oct every 2 weeks

    From 20th July to 3rd October, keep the bed evenly moist in dry spells and hoe off weeds before they compete with the crop. Check the mesh stays tight after rain and wind, and water at the base rather than over the foliage.

  6. 06

    Harvest Roots

    20 Oct to 31 Jan

    Lift roots from 20th October once they are a good size, then keep harvesting through 31st January. In light, free-draining soil you can leave some in the ground and take them as needed, but lift them before the roots become coarse.

Companion plants

Tap a plant to see why it works (or doesn't) with Swede.

Good companions

Plants to avoid

Why companion planting matters

Companion planting can deter pests, improve pollination, and make better use of space. Some plants confuse pests or attract beneficial insects; others improve soil or offer shade to neighbours that need it.

Suggested varieties

Popular varieties of Swede to consider

Joan

A reliable modern swede with good-sized, round roots and steady autumn cropping.

Best of All

An old favourite with good flavour and dependable roots for the kitchen garden.

Marian

A hardy, well-fleshed variety suited to UK conditions and winter harvesting.

Swede guides by town

See how Swede timing shifts in other towns with different frost dates.